acute triangle: a triangle with 3 acute angles

polygon: a closed plane figure with sides made from straight line segments

equilateral triangle: a triangle with all equal sides and angles

quadrilateral: a polygon with four sides.

hexagon: a polygon with six sides

rectangle: a parallelogram with all right angles

isosceles triangle: a triangle with two sides that are congruent

rhombus: a parallelogram with all sides the same length

obtuse triangle: a triangle with one obtuse angle

right trapezoid: a trapezoid with one right angle

octagon: a polygon with eight sides

right triangle: a triangle with one right angle

parallelogram: a polygon with two pairs of parallel sides

scalene triangle: a triangle with no sides the same length

pentagon: a polygon with 5 sides

square: a parallelogram with all sides the same length and all right angles

trapezoid: a quadrilateral with one set of parallel lines

kite: a quadrilateral where adjacent sides are congruent.